1. Field of the Invention
The present invention relates to a sealing assembly used for a wheel bearing of automobiles. More specifically, the present invention relates to a sealing assembly which prevents ingress of contaminating agents such as dirty water or dust into a bearing, and includes an inner annular element, an outer annular element, a seal rubber, and grease.
2. Description of Related Art
Heretofore, many types of sealing elements have been developed, and exemplary of the known type of sealing element is that shown in FIG. 3.
FIG. 3 is a sectional view of a conventional sealing assembly 100. The conventional seal assembly includes an inner annular element 132 opposed by an outer annular element 134. The inner annular element 132 includes an inner surface 144 and an outer surface 146 thereon. A seal rubber 136 is interposed between the inner annular element 132 and the outer annular element 134 and includes lips 140 projecting from the seal rubber 136. The lips 140 are only formed to contact the inner surface 144 of the inner annular element 132. As also shown, grease 142 is inserted between the inner surface 144 of the inner annular element 132 and the lips 140 of the seal member 136.
In comparison with the present invention which will be described below, the amount of grease 142 contained in the known sealing assembly 100 is much smaller than that of the present invention, and the potential risk to abrasion and noise by the ingress of dust or water is much higher due to the simple shape of the lips 140 in the known art.
In the case of mounting the conventional bearing employing the known xe2x80x9cpack seal typexe2x80x9d sealing assembly as shown in FIG. 3, certain problems are raised. For example, the ingress of contaminating agents such as dust or dirty water might cause not only wear and distortion of lips 140 but also abrasion of the inner ring or outer ring of the bearing and noise occurred by contaminating agents stuck to bearing balls.
Therefore, a need in the art exists for an improved sealing assembly of the type discovered by the inventor.
Accordingly, it is a primary object of the present invention to provide a sealing assembly which is superior in preventing the ingress of contaminating agents such as dirty water or dust therein.
It is a further object of the present invention to provide a sealing assembly which is a xe2x80x9chigh pack seal typexe2x80x9d sealing assembly instead of a xe2x80x9cpack seal typexe2x80x9d sealing assembly.
It is yet another object of the present invention to provide a high pack seal type sealing assembly having an inner annular element of a characteristic shape, the shape including an inner surface and an outer surface.
It is a further object of the present invention to provide a high pack type sealing assembly in which a seal rubber includes a plurality of projecting lip portions, at least one of which is in contact with an outer surface of the inner annular element.
It is still a further object of the present invention to provide a sealing assembly having improved isolation of the bearing by preventing the leak of grease in the sealing assembly and ingress of contaminating agents into the bearing.
These and other objects of the present invention are achieved by providing a sealing assembly used for a wheel bearing of automobiles in order to prevent ingress of contaminating agents such as water or dust into a bearing. The sealing assembly includes an inner annular element, an outer annular element, a seal rubber, and grease. More particularly, the sealing assembly adapts a xe2x80x9c]xe2x80x9d-shaped inner annular element. Additionally, the seal rubber includes a plurality of projecting lips and an uppermost lip of the seal rubber comes in contact with an outer surface of the inner annular element. As a result, it is possible to enlarge the grease containing area and improve the isolation of the bearing by preventing the leak of grease from the sealing assembly and ingress of contaminating agents into the bearing. The primary characteristics therefore are the xe2x80x9c]xe2x80x9d-shaped inner annular element, and modifying the shape of lips projected on the seal rubber interposed between the inner annular element and the outer annular element so as to improve the performance of the bearing by isolating the bearing from the surrounding environment.
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: